<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script type="text/javascript">
    function demo() {
        console.log(this)
    }

    demo()

    const x = demo.bind({a: 1, b: 2})
    x()
</script>
</body>
</html>